rubocop -a can autocorrect many kinds of issues.

ActiveRecord update_all does not touch updated_at

byebug

If one wants to run iex without starting any applications iex -S mix run --no-start is very handy

For models A and B, if A has_one B, then A.new.b.build wont work. You have to say A.new.build_b.

Sidekiq processes jobs in a multithreaded process. Which means there is no guarantee that the jobs that are enqueued will processed in the same order. So you'd need to consider the aspect of context switch that can happen and thus make sure that the worker code is thread safe.

Today I came to know that the name of process which takes care of clipboard is called pboard on mac. If clipboard is acting funny, just kill this process!

while tesing with enzyme if you are unit testing your component method with component.instance().methodName() always double check if the method that you are testing have access to "this" variable manually. Currently even if it does not have "this" access the test will pass